package top.quercus.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.util.Random;

@Controller
@RequestMapping("/captcha")
public class CaptchaController {
    @RequestMapping("/checkCaptcha")
    @ResponseBody
    public boolean checkCaptcha(String userCode, HttpSession session) {
        //处理请求
        //获取Session中存储的系统验证码
        String sysCode = (String) session.getAttribute("randStr");
        //4.响应结果
        return sysCode.equals(userCode);
    }

    @RequestMapping("/getCaptcha")
    public void getCaptcha(HttpServletRequest req, HttpServletResponse resp,HttpSession session) {
        // 在内存中创建图象
        int width = 110, height = 30;
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        // 获取图形上下文
        Graphics g = image.getGraphics();
        // 生成随机类
        Random random = new Random();
        // 设定背景色
        g.setColor(getRandColor(200, 250));
        g.fillRect(0, 0, width, height);
        // 设定字体
        g.setFont(new Font("Times New Roman", Font.PLAIN, 20));
        // 随机产生155条干扰线，使图象中的认证码不易被其它程序探测到
        g.setColor(getRandColor(160, 200));
        for (int i = 0; i < 155; i++) {
            int x = random.nextInt(width);
            int y = random.nextInt(height);
            int xl = random.nextInt(12);
            int yl = random.nextInt(12);
            g.drawLine(x, y, x + xl, y + yl);
        }
        // 取随机产生的认证码(6位数字)
        StringBuilder sRand = new StringBuilder();
        for (int i = 0; i < 6; i++) {
            String rand = String.valueOf(random.nextInt(10));
            sRand.append(rand);
            // 将认证码显示到图象中
            g.setColor(new Color(20 + random.nextInt(110), 20 + random
                    .nextInt(110), 20 + random.nextInt(110)));
            // 调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
            g.drawString(rand, 13 * i + 6, 16);
        }
        // 图象生效
        g.dispose();

        try {
            ImageIO.write(image, "JPEG", resp.getOutputStream());
        } catch (Exception e) {
            System.out.println("验证码图片产生出现错误：" + e);
        }
        //保存验证码到Session
        session.setAttribute("randStr", sRand.toString());
    }

    /*
     * 给定范围获得随机颜色
     */
    private Color getRandColor(int fc, int bc) {
        Random random = new Random();
        if (fc > 255)
            fc = 255;
        if (bc > 255)
            bc = 255;
        int r = fc + random.nextInt(bc - fc);
        int g = fc + random.nextInt(bc - fc);
        int b = fc + random.nextInt(bc - fc);
        return new Color(r, g, b);
    }
}



